The present invention relates to a showcase in which a display chamber is constituted in an insulation wall and in which commodities are displayed in the display chamber while cooling the commodities. More particularly, it relates to illumination in a display chamber.
Heretofore, as this type of showcase, there is an open showcase 100 as disclosed in, for example, Japanese Patent Application Laid-Open No. 5-146346 (the patent document) and as shown in FIG. 18. FIG. 18 is a vertical side view showing the conventional open showcase 100. In the open showcase 100, cold air is discharged to a suction port 104 formed in the lower edge of an opening 102 from a discharge port 103 formed in the upper edge of the opening 102 in an insulation wall 101 having a substantially U-shaped section, whereby a cold air curtain is formed in the opening 102. In consequence, the inside of a display chamber 105 surrounded with the insulation wall 101 is cooled at a predetermined temperature. Then, a plurality of fluorescent lamps 108 are attached to a canopy 107 positioned outside the upper edge of the opening 102, the opposite side edges of the opening 102, the lower surfaces of the front parts of shelves 106 and the like, to illuminate the display chamber 105 and the showcase 100 itself.
However, in the conventional open showcase 100, the fluorescent lamps 108 used as illumination devices are obliged to be replaced owing to the lowering of luminance and a lighting defect due to deterioration with an elapse of years. Therefore, a user is forced to perform the replacement operation of the fluorescent lamps 108, which causes a problem that the operation becomes laborious. A new fluorescent lamp 108 for the replacement needs to be stocked, and the storage place of the fluorescent lamp 108 needs to be secured. Furthermore, the fluorescent lamp 108 contains mercury, so that there is a problem that the used fluorescent lamp 108 cannot easily be discarded.
Moreover, to attach the fluorescent lamp 108 in the display chamber 105, components such as a socket and a stabilizer are required, and hence the attachment places of not only the fluorescent lamps but also the sockets, the stabilizers and the like need to be secured in attachment positions. Furthermore, wires have to be connected so as to supply powers to the respective fluorescent lamps, whereby there are problems that assembly operability deteriorates and that the increase of the number of the components and the steep rise of production cost are caused. In addition, the fluorescent lamp has a problem that the lamp flickers owing to the use of an alternate current, and hence eyes are adversely affected.